This invention relates generally to automated ultrasound and eddy current inspection systems, and more particularly to automated inspection systems for turbine and generator rotors and wheels.
Manual inspections of rotor forgings and related components have been performed for many years to inspect for flaws in the forgings. Because of the difficulties and inaccuracies associated with manual ultrasonic and eddy current tests, two separate manual tests are typically performed on rotors to increase the reliability of the inspection.
Manual ultrasonic inspection of rotor forgings include a radial test from the periphery of the rotor forging directed toward the center of the forging. An inspector watches the ultrasonic test instrument looking for reflectors. The operator then peaks the reflector and records its location and amplitude. An inattentive inspector an easily miss indications due to momentary distractions, an incorrect setup, as well as monotony and tedium.
In some cases a semi-automated system has been used to inspect rotor forgings. The system captured the inspection waveforms and permitted an inspector to identify possible flaw indications located within the rotor. The inspector then returned to the identified areas and performed a manual ultrasonic inspection to confirm the flaw indication as well as determine the peak amplitude of the indication. The peak amplitude is used to determine the size of embedded flaw. The semi-automated system requires a manual exam to verify defect amplitude and location.